Table of Contents
ISRN Nephrology
Volume 2013, Article ID 673795, 6 pages
http://dx.doi.org/10.5402/2013/673795
Research Article

Cystatin C at Admission in the Intensive Care Unit Predicts Mortality among Elderly Patients

1Universidade Federal de São Paulo, Botucatu Street, n740, Vila Clementino, 04023-062 São Paulo, SP, Brazil
2Hospital Israelita Albert Einstein, Albert Einstein Avenue, n627, Morumbi, 05652-900 São Paulo, SP, Brazil
3Division of Nephrology, Tufts University, Boston Avenue, n419, Medford, MA 02155, USA

Received 3 August 2013; Accepted 11 September 2013

Academic Editors: C. Escobar, M. Léone, M. Merta, and E. G. Mik

Copyright © 2013 Maria Aparecida Dalboni et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Introduction. Cystatin C has been used in the critical care setting to evaluate renal function. Nevertheless, it has also been found to correlate with mortality, but it is not clear whether this association is due to acute kidney injury (AKI) or to other mechanism. Objective. To evaluate whether serum cystatin C at intensive care unit (ICU) entry predicts AKI and mortality in elderly patients. Materials and Methods. It was a prospective study of ICU elderly patients without AKI at admission. We evaluated 400 patients based on normality for serum cystatin C at ICU entry, of whom 234 (58%) were selected and 45 (19%) developed AKI. Results. We observed that higher serum levels of cystatin C did not predict AKI ( versus  mg/L; ). However, it was an independent predictor of mortality, H.R. = 6.16 (95% CI 1.46–26.00; ), in contrast with AKI, which was not associated with death. In the ROC curves, cystatin C also provided a moderate and significant area (0.67; ) compared to AKI (0.47; ) to detect death. Conclusion. We demonstrated that higher cystatin C levels are an independent predictor of mortality in ICU elderly patients and may be used as a marker of poor prognosis.